I stumbled across this the other day and began to wonder if this could be causing so many people's low space issues after they tried all the other fixes we have suggested (email trash, cache cleaning etc.) If you go into Maps and do menu>more>cache settings Look at how much space your map tiles are taking up. I'm a light maps user and I had 20MB of map tiles stored. I can only imagine one who uses the phone for navigation frequently would have a large map tile cache. You can clear the map tile cache and it will download your maps again as you need them. If you are having low space issues give this a try and see if it will help. PS...clearing the cache in the "manage application" setting will NOT clear the map tile cache.